The present invention relates generally to an image forming device, and particularly to devices that determine conditions within the image forming device.
To ensure high quality image formation, precise control of the speed and position of media sheets is required as they are transported along a media path. In addition, many parameters of the image-forming process, such as the media sheet transfer speed, the operating temperature of a fuser, and the like, depend on the type of media. For example, opaque media such as bond paper may require different image formation and fixing parameters than other media, such as transparencies. Hence, it may be necessary that both the position and the type of media sheet (e.g., opaque sheet or transparency) be accurately sensed.
To detect these and other types of conditions, a given image forming device may employ a plurality of media sensors such as electromechanical or optical sensors. For example, a given image forming device may use a first media sensor to detect the media sheet width, a second media sensor to detect the position of a media sheet, and a third media sensor to detect the media sheet type (e.g., opaque sheet or transparency). Still an additional sensor may be used to detect whether a media input tray is in a position to introduce media sheets into the media path.
The number of sensors utilized within the image forming device raises several concerns. Chief among them is the increased costs passed to the consumer. Additionally, a greater number of sensors lead to greater complexity, and thus, the reliability of a given apparatus might suffer. Image forming devices, however, should be constructed in an economical manner without impinging upon reliability. Both cost reduction and improved system reliability may be obtained by integrating the functions of a plurality of media sensors into fewer components.